Identifying the causes of sea level changes

Global mean sea-level rise has increased from a rate of a few centimetres per century over the past few millennia to a few decimetres per century in the past few decades. This ten fold increase in rate is due to climate change and is dominated by melting of land ice and warming of ocean water. The current warming trend is expected to continue and so global mean sea level will continue to rise. In this article, we review recent advances in our understanding of past sea-level changes on decadal to millennial timescales to consider how well future changes can be constrained. The majority of studies suggest that global mean sea-level rise will most likely be less than 1 m over the 21st century. Importantly, there will be significant departures from the global mean by several decimetres in many areas. As a consequence, future research should be targeted at better constraining the spatial variability in future changes so that high-risk areas can be identified